A resource is for example an application creating different events. An event is an undirected message that informs about a change in a system's state, i.e. a change of one or more of the system's Service Data Elements. Service Data is a set of attributes (name-value pairs) that define the system's state. One Service Data Element is a single attribute (name-value pair) out of a system's Service Data. A number of distributed resources is managed by a management system comprising a workflow engine that can execute management workflows in order to actively control distributed resources.